Sador was in his youth a woodsman, and he learned how to carve and craft things out of wood. In FA 455 the Dagor Bragollach (Battle of Sudden Flame) broke out, and Fingolfin, High King of the Ñoldor, summoned him to the war against Morgoth. Sador arrived at the battle too late, but came soon enough to carry the bier of Hador, his lord. He decided afterward to become a soldier. In FA 462, he defended Barad Eithel, and soon after stopped being a soldier. He began woodworking again, but misfortune was his lot, for he accidentally cut off his right foot with an axe.
Sador found service with Húrin, and was a woodcrafter for him. He met Túrin, and was given the name Labadal, which translates to 'hopafoot' in the Sindarin tongue. This name was not given in scorn, but pity. Túrin also gave Sador the elven knife that he received for his birthday. Sador would craft carvings of men, beasts, and other things, and teach Túrin morals.
Morwen, Húrin's wife, was not fond of Sador. She said that he did not work fast, and spent too much time "on trifles unbidden". However, Húrin was moved by Túrin's pity for Sador, and gave him the task of carving a chair for his hall.
Before the Nirnaeth Arnoediad (Battle of Unnumbered Tears), Húrin left to go to war. Sador began serving Morwen. Sador did not fight in the Battle of Unnumbered Tears, and was dismayed that he could not do so, and "die a valiant death." When Túrin left to go to Doriath he first talked to Sador. Sador talked with Túrin about the necessity of his departure. Túrin was sad, but understood. Sador urged him to take back the elven knife. Túrin refused, saying that he would get many things like it in Doriath.
Sador stayed in the house of Morwen for a long while but after the loss of the Nirnaeth Arnoediad, he was enslaved by the Easterlings just like the rest of the Men of Dor-lómin. After 13 years, Túrin returned from Doriath and Nargothrond, now a very tall man. Sador (who was now old) met Túrin at Aerin's house, and participated in a rebellion against the Easterlings (led by Brodda) that had taken over the area. During the uprising, Sador was fatally wounded by the enemy. He was, however, able to say his final words to Túrin before perishing.
- The Silmarillion: Quenta Silmarillion, "Of Túrin Turambar"
- The Children of Húrin
- Unfinished Tales: Narn i Chîn Húrin